In the prior arts, various mode changing systems have been proposed in which .[.movable components.]. .Iadd.operating members .Iaddend.for a cassette tape recorder such as a head base plate and a pinch roller are selectively moved to a position corresponding to the selected one of modes such as stopping, fast forwarding rewinding, pausing, cueing and playing or recording. However, the prior mode changing system which is of manually operating type, has an operating lever provided with lock means, which causes the system to be complicated in its construction and to have a number of parts. Thus, the system is not only expensive, but also has a difficulty to be handled. In addition thereto, it is difficult to remote-control the system. Another prior mode changing system which is of electrically operating type, has plunger means which is not always positive in its operation and has a temperature highly increasing during its operation. Thus, the system is disadvantageously ineffective and also tends to generate a noise while it is operated.